Electrode for rechargeable lithium battery and rechargeable lithium battery including same

Abstract

An electrode for a rechargeable lithium battery includes a current collector and an active material layer on the current collector, the active material layer including an active material and carbon nanotubes, and the carbon nanotubes having a Raman R value of about 0.8 to about 1.3 and an average length of about 40 μm to about 250 μm. The Raman R value refers to an intensity ratio R=Id/Ig obtained from a peak intensity (Ig) (G, about 1580 cm−1) and a peak intensity (Id) (D, about 1350 cm−1) in a Raman spectrum analysis.

What is claimed is: 
     
         1 . An electrode for a rechargeable lithium battery, the electrode comprising
 a current collector; and   an active material layer on the current collector,   wherein the active material layer comprises an active material and carbon nanotubes,   the carbon nanotubes have a Raman R value of about 0.8 to about 1.3 and an average length of about 40 μm to about 250 μm, and   the Raman R value refers to an intensity ratio R=Id/Ig, Ig being a peak intensity G at about 1580 cm −1 , and Id being a peak intensity D at about 1350 cm −1  in a Raman spectrum analysis.   
     
     
         2 . The electrode of  claim 1 , wherein the Raman R value is in a range of about 0.9 to about 1.15. 
     
     
         3 . The electrode of  claim 1 , wherein the carbon nanotubes have an average length of about 70 μm to about 250 μm. 
     
     
         4 . The electrode of  claim 1 , wherein the carbon nanotubes have an average length of about 100 μm to about 250 μm. 
     
     
         5 . The electrode of  claim 1 , wherein the carbon nanotubes have an average diameter of about 1 nm to about 20 nm. 
     
     
         6 . The electrode of  claim 1 , wherein the carbon nanotubes have volume density of less than or equal to about 0.1 g/cm 3 . 
     
     
         7 . The electrode of  claim 1 , wherein the carbon nanotubes are one or more selected from the group consisting of single-walled carbon nanotubes, double-walled carbon nanotubes, and multi-walled carbon nanotubes. 
     
     
         8 . The electrode of  claim 1 , wherein the weight of the carbon nanotubes is less than or equal to about 1 wt % based on the total weight of the active material layer. 
     
     
         9 . The electrode of  claim 1 , wherein the active material layer further comprises nanocarbon. 
     
     
         10 . The electrode of  claim 9 , wherein the nanocarbon has an average particle diameter of about 5 nm to about 100 nm. 
     
     
         11 . The electrode of  claim 9 , wherein a weight ratio of the carbon nanotubes and the nanocarbon is in a range of about 3:1 to about 1:3. 
     
     
         12 . The electrode of  claim 9 , wherein the total weight of the carbon nanotubes and the nanocarbon is less than or equal to about 1.5 wt % based on the total amount of the active material layer. 
     
     
         13 . The electrode of  claim 1 , wherein the active material is a positive active material. 
     
     
         14 . The electrode of  claim 1 , wherein the active material is a negative active material. 
     
     
         15 . The electrode of  claim 14 , wherein the negative active material comprises silicon. 
     
     
         16 . A rechargeable lithium battery, comprising:
 a positive electrode;   a negative electrode;   a separator between the positive electrode and the negative electrode; and   an electrolyte solution,   wherein at least one selected from the group consisting of the positive electrode and the negative electrode is the electrode of  claim 1 .   
     
     
         17 . The rechargeable lithium battery of  claim 16 , wherein the positive electrode is the electrode for the rechargeable lithium battery.